The invention discloses a sail cable fastening system, comprising recycled sails and cables for fixing the sails. Four sail eye plates are disposed at a joining part of transverse frames and longitudinal frames of the sale, and are arranged at the same panel, parallel to a deck and are used as four top points of a small rectangle. The deck is provided with four deck eye plates, which are corresponding to the sail eye plate and are used as four top points of a large rectangle. The small rectangle is disposed in an area surrounded by the large rectangle, and the edges of the big rectangle are incorrespondingly parallel with the edges of the small rectangle. The four deck eye plates and the four sail eye plates are connected one by one in a manner that the top points of the large rectangle correspond to those of the small rectangle through four cables. The invention is advantageous in that the damage of the sails to a base can be greatly reduced, and cables can be saved.